1. Field of Invention
The present invention relates to a wireless remote control lighting unit, a wireless remote control lighting system and a control method thereof, in particular to such wireless remote control lighting unit, wireless remote control lighting system and control method that do not require a complicated handshaking process for addressing.
2. Description of Related Art
FIG. 1 explains the operation for wireless control of lighting units. Lighting units 10A, 10B, and 10C have different addresses; for example, the address of the lighting unit 10A is AAA, that of the lighting unit 10B is BBB, and that of the lighting unit 10C is CCC. Through radio frequency (RF), infrared (IR), or other carriers, signals containing addresses, instructions and so on are transmitted and received between a remote controller 11 and the lighting units 10A, 10B, and 10C, as the arrows of dash lines shown in this figure. The instructions transmitted by the remote controller 11 may be to turn on or turn off a lighting unit, to increase or decrease its brightness (dimming) and so on. In FIG. 1, as an example, the remote controller 11 transmits a signal AAAXXX, and it means that an instruction XXX is sent to the lighting unit 10A with the address AAA. After the address and instruction are transmitted by the remote controller 11, each of the lighting units 10A, 10B, and 10C receives the same information of the address and the instruction and checks whether the received address matches its address. If it is affirmative, the lighting unit (10A) will execute the instruction XXX; if it is negative, the corresponding lighting unit (10B, 10C) will ignore the instruction XXX.
In view of the above, each of the lighting units 10A, 10B, and 10C must have an address. This creates an issue as to how an address can be assigned to a lighting unit. One way to set an address to a lighting unit is to do so when the lighting unit is being manufactured. However, this requires a global address management system, and the remote controller 11 needs to be set again every time when a user replaces any lighting unit with a new one, which is obviously quite inconvenient. If the address is not set for the lighting unit when it is in manufacture, the lighting unit must have both transmitter and receiver circuits for bidirectional handshaking with the remote controller 11 to establish a link, and the remote controller 11 also must have both transmitter and receiver circuits for the handshaking process; this increases the hardware cost.
FIG. 2A shows an example of a prior art action flowchart which requires a bidirectional handshaking process to establish a link, wherein the address is set to the lighting unit after the light unit is installed. As shown in the figure, after power on, the lighting unit and the remote controller 11 enter an address setting mode to set the address of the lighting unit. After the lighting unit is set with an address, it enters an action mode to receive and execute the instructions transmitted by the remote controller 11, as shown in FIG. 1.
The disadvantages of the foregoing prior art are: First, in the address setting process, it requires complicated handshaking steps between the lighting unit and the remote controller 11 to check and avoid the used addresses, assign an unused address to an unaddressed lighting unit, check acknowledgement from the lighting unit, . . . , etc.; the process is very complicated. Second, the lighting unit and the remote controller 11 must be equipped with both receiver circuits and transmitter circuits, so the hardware cost is increased. In addition, such system always first enters the address setting mode when power on, so the action time is delayed. Furthermore, if the address is stored in a non-volatile memory instead of a volatile memory, the repeated address settings consume the write endurance and reduce the lifetime of the non-volatile memory.
FIG. 2B shows another prior art action flowchart. After power on, a lighting unit always first enters the action mode, and it enters the address setting mode only when it receives a specific code or certain verified information, which indicates that an unaddressed lighting unit has been installed or some other events that require renewing the address or repairing the address link with the remote controller 11. However, this approach still requires similar complicated handshaking steps, and both the lighting unit and the remote controller 11 need to be equipped with transmitter and receiver circuits, requiring a higher cost in terms of the number and specification of the circuit devices.
U.S. Patent Publication No. 2006/0049935 discloses a method for wireless control of a lighting unit. In this patent, it is the lighting unit that transmits its address and it is the remote controller that receives the address to construct the address link. However, this still does not overcome the above drawbacks: the requirement of bi-directional transceivers in both the lighting unit and the remote controller and the complicated handshaking steps for address setting.
In view of the above, the present invention proposes a wireless remote control lighting unit, a wireless remote control lighting system and a control method to overcome the foregoing drawbacks.